This application claims the benefit of German Application DE P 10040106.6, filed Aug. 17, 2000, herein incorporated by reference.
The present invention relates generally to a winding device for a textile machine that produces cheeses of wound yarn and, more particularly, to such a winding device which comprises a creel having opposed tube receiving plates for holding a cheese tube therebetween, a yarn traversing device comprising a separate traversing drive, and a speed-regulatable drive device integrated in the creel for movement in a bearing housing of the creel and connected to one of the tube receiving plates.
Such winding devices for textile machines are generally known, e.g., in conjunction with the production of cheeses of xe2x80x9cprecision windingxe2x80x9d and xe2x80x9cstep [stage] precision windingxe2x80x9d types.
Subsequently published German Patent Publication DE 199 08 093.3 describes, e.g., a winding device in which a cheese held in a creel is directly driven by a drive motor integrated in the creel. The cheese rests on a pressure roller, sometimes referred to as a billy-roller, that is not driven itself. The traversing of the yarn to be wound takes place by means of a finger-like yarn guide loaded by a separate drive. The two drives can be controlled via an appropriate control device in such a manner that a defined, pre-selectable winding relationship, specifically a defined ratio, is always achieved.
Since a cheese must be brought to a standstill rather frequently in the overall course of winding a full cheese, e.g. when a feeding cop slows down, upon a yarn break or after a controlled yarn cleaner cut, the known winding device also comprises a pneumatically loadable braking device integrated in the cheese drive. This known braking device is comprised of a brake lining arranged on the stator housing and adapted to rotate in unison with said housing, against which brake lining a contact surface, designed as a brake disk, of a tube receiving plate can be pneumatically pressed. The braking force produced thereby rapidly brings the cheese to a standstill.
However, the known winding device has a number of disadvantages. Specifically, both the rotating brake disk and the stationary brake lining are subject to significant wear and are therefore relatively maintenance-intensive. In addition, the accumulating brake dust can readily pass into the axial sliding guide of the cheese drive as well as into the bearing of the electromotor and result in a breakdown of these components.
Moreover, winding devices are known, e.g. in German Patent Publication DE 198 36 701 A1 in which devices a grooved drum that drives the cheese and at the same time traverses the yarn is electrically braked to a standstill after the cheese has been lifted off the drum. To this end the drive motor of the grooved drum is loaded with a braking current that is usually a multiple of the rated nominal current of the drive motor.
Accordingly, in view of the above-described state of the art, it is an object of the invention to improve the known winding devices.
Basically, the present invention addresses this objective by a cheese winding device essentially comprising a creel having opposed tube receiving plates for holding a cheese tube therebetween for rotation in a winding direction, a yarn traversing device comprising a separate traversing drive, and a speed-regulatable drive device integrated in the creel. The drive device is arranged in a sliding sleeve mounted in a bearing housing of the creel and is connected to one of the tube receiving plates for movement pneumatically against a displacement force of spring elements for selective movement of one of the tube receiving plates outwardly in a creel opening direction. A braking arrangement is also provided for loading the drive device with a braking current for braking the cheese by producing a moment opposite the direction of winding rotation of the cheese.
The present invention has the particular advantage that the braking device associated with the winding device, on the one hand, operates almost without wear and, on the other hand, reliably brakes the cheese in an extremely short time to a standstill. The spring elements that act on the sliding sleeve that receives the drive device assure that the cheese tube held non-positively between the tube receiving plates is held in a very largely slip-free manner during acceleration and also during braking. However, at the same time, the design of the invention also assures that the creel can be opened without problems at any time as needed. That is, the sliding sleeve, and therewith the drive device connected to one of the tube receiving plates, can be pneumatically loaded in such a manner that the sliding sleeve can be moved against the displacement force of a spring element into the bearing housing. The tube receiving plate concerned is shifted outward thereby so that the cheese tube of the cheese and therewith the cheese are reliably released.
In order to brake the cheese, the drive device is first loaded with a braking current by appropriately regulating an end stage, which braking current generates a moment counter to the direction of rotation of the cheese and can be a multiple of the rated current, if required. The braking moment generated thereby in the drive device assures that even large-volume cheeses are reliably braked to a standstill in an extremely short time.
In a preferred embodiment of the present invention, the drive device is designed as an electronically commutated direct-current motor whose rotor is directly connected to one of the tube receiving plates. A drive device designed in such a manner constitutes a compact, high-performance drive that is also distinguished by a good price/performance ratio.
Preferably, the sliding sleeve that receives the drive device is loaded by at least one spring element whose spring power is directed parallel to the axis of rotation of the drive device toward the middle of the creel. That is, the spring element assures that a cheese arranged between the tube receiving plates is reliably clamped.
It is further preferred that the spring elements are designed as helical springs and act on the sliding sleeve. The helical springs, preferably two, extend into corresponding receiving bores of the sliding sleeve and are supported on a stationary bearing housing wall. The movably supported sliding sleeve, in which the drive device is arranged, is permanently loaded, as already mentioned above, by spring elements in the direction of the middle of the creel. That is, the spring elements assure with a high pressing force that a cheese tube arranged between the tube receiving plates is reliably clamped at all times. The distribution or arrangement of the spring elements is selected in such a manner that an attack of force from one side and therewith a tilting of the sliding sleeve inside the bearing housing is excluded.
In addition, an advantageous embodiment of the invention provides that an annular space is located between the sliding sleeve receiving the drive device and the bearing housing of the creel, which space can be loaded in a defined manner with compressed air. That is, the sliding sleeve can be moved in such a manner against the spring power of the spring elements attacking the sliding sleeve by loading this annular space in a defined manner with compressed air that one of the tube receiving plates is shifted outward and as a result a cheese tube that was held up to that time between the tube receiving plates is released.
The annular space of the sliding sleeve is connected via an electromagnetic valve that is preferably designed as a 3/2-port directional control valve to a compressed-air source of the textile machine. The use of such a proven electromagnetic valve makes possible in a simple and reliable manner a defined control of the particular creel by means of a winding head computer. Thus, the sliding sleeve movably supported in a bearing housing of the creel can be pneumatically loaded in such a manner at any time as required that one of the tube receiving plates is actuated in a creel opening direction.
In order to also be able to open the creel manually, the previously described directional control valve also comprises a manual actuation control. It is possible to open the creel manually with this manual actuation independently of the winding head computer, e.g., to remove a specimen cheese.
Finally, an abutment is provided on the creel into which abutment a corresponding tool can be inserted. If necessary, the abutment makes possible a purely manual displacement of the sliding sleeve loaded by spring power, so that it is possible to open the creel even if the compressed air is lacking in the textile machine or if there is a significant drop in the compressed air.
Further details of the invention can be gathered below from an exemplary embodiment explained in the drawings.